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How would you count occurrences of a string (actually a char) within a string?
... found that Richard Watson's solution is fastest in most cases. That's the table with results of every solution in the post (except those use Regex because it throws exceptions while parsing string like "test{test")
Name | Short/char | Long/char | Short/short| Long/short | Long/long |
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Prevent jQuery UI dialog from setting focus to first textbox
...s>
In the documentation, the focus logic is explained (just under the table of contents, under the title 'Focus'):
Upon opening a dialog, focus is automatically moved to the first item
that matches the following:
The first element within the dialog with the autofocus attribute
T...
Web scraping with Python [closed]
...utifulSoup(urllib2.urlopen('http://example.com').read())
for row in soup('table', {'class': 'spad'})[0].tbody('tr'):
tds = row('td')
print tds[0].string, tds[1].string
# will print date and sunrise
share
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unresolved reference to object [INFORMATION_SCHEMA].[TABLES]
I've created a UDF that accesses the [INFORMATION_SCHEMA].[TABLES] view:
3 Answers
3...
How do I create a unique constraint that also allows nulls?
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This very problem hits ADO.NET DataTables too. So even that I can allow nulls in the backing field using this method, the DataTable won't let me store NULLs in a unique column in the first place. If anyone knows a solution for that, please post it here
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Do AJAX requests retain PHP Session info?
...session data, and it's possible that the main page request is locking that table, preventing the AJAX request from accessing it.
– Buttle Butkus
Aug 7 '19 at 3:57
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SQL Server 2008: how do I grant privileges to a username?
I need to be able to establish an ODBC connection through SQL Server authentication.
3 Answers
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On duplicate key ignore? [duplicate]
...).
Instead, since in your example tag is the unique key, use:
INSERT INTO table_tags (tag) VALUES ('tag_a'),('tab_b'),('tag_c') ON DUPLICATE KEY UPDATE tag=tag;
on duplicate key produces:
Query OK, 0 rows affected (0.07 sec)
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How to count TRUE values in a logical vector
...values.
See for example:
z <- c(TRUE, FALSE, NA)
sum(z) # gives you NA
table(z)["TRUE"] # gives you 1
length(z[z == TRUE]) # f3lix answer, gives you 2 (because NA indexing returns values)
So I think the safest is to use na.rm = TRUE:
sum(z, na.rm = TRUE) # best way to count TRUE values
(whi...
When/Why to use Cascading in SQL Server?
...eal key rather than a surrogate key (identity/autoincrement column) across tables.
The canonical example for Cascade Update is when you have a mutable foreign key, like a username that can be changed.
You should not use Cascade Update with keys that are Identity/autoincrement columns.
Cascade Updat...